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991.
The Japenese eel, Anguilla japonica, is generally assumed to be composed of a single population with wide distribution range, and some genetic studies using allozyme or mitochondrial DNA methods supported this population model. However, one genetic study suggested the existence of multiple populations in this species, and thus, more detailed studies on the population structure is needed. Here we characterized a total of 11 microsatellite markers of the Japanese eel. These will serve as powerful tools for detailed population study for the Japanese eel, though two of them showed the significant departure from the Hardy–Weinberg expectations. 相似文献
992.
Satoshi Iwao Nobuko Iwao Denis C. Muller Dariush Elahi Hiroshi Shimokata Reubin Andres 《Obesity (Silver Spring, Md.)》2001,9(11):685-695
Objectives: To examine the power of the combined measurements of body mass index (BMI) and waist circumference (WC) for the prediction of abnormality in coronary heart disease risk factors and to determine whether the additional measurement of WC is predictive in older men and women. Research Methods and Procedures: 1190 men and 751 women of the Baltimore Longitudinal Study of Aging were dichotomized into younger (<65 years) and older (65+ years) age groups. Coronary risk factors in the realms of glucose/insulin metabolism, blood pressure, and plasma lipids were assessed. The relationship of BMI and WC, singly and combined, to 10 risk factors for coronary heart disease was examined. Results: In younger and older men and women, BMI and WC are highly correlated (0.84 to 0.88). BMI and WC are also significantly correlated to all 10 coronary risk factors in younger men and women and to 8 of the 10 in the older men and women. Both partial correlation and logistic regression analyses revealed a modest but significant improvement in the prediction of coronary risk in younger men and women by WC after controlling for the level of BMI. There was no improvement in the older subjects. Discussion: WC adds only modestly to the prediction of coronary risk in younger subjects once BMI is known, and adds nothing to the production of risk in older subjects. 相似文献
993.
Tomoki Matsuda Makoto Fujikawa Mitsuru Haruki Xiao-Feng Tang Satoshi Ezaki Tadayuki Imanaka Masaaki Morikawa Shigenori Kanaya 《Extremophiles : life under extreme conditions》2001,5(3):177-182
Interactions of TBP-interacting protein (TIP26), TBP, and TFB from a hyperthermophilic archaeon Thermococcus kodakaraensis KOD1 with TATA-DNA were examined by electrophoretic mobility shift assay. Tk-TFB formed a ternary complex with Tk-TBP and TATA-DNA. Tk-TIP26 did not inhibit the formation of this ternary complex, but interacted with it to form a TIP26/TFB/TBP/DNA quaternary complex. This interaction is rather weak, and a large excess of Tk-TIP26 over Tk-TBP is required to fully convert the TFB/TBP/DNA ternary complex to the quaternary complex. However, determination of the concentration of Tk-TIP26 and Tk-TBP in KOD1 cells by Western blotting analysis indicated that the concentration of Tk-TIP26 is approximately ten times that of Tk-TBP, suggesting that the quaternary complex might also form in vivo. 相似文献
994.
995.
Kazuhiro Usui Yoji Sasahara Ryushi Tazawa Koichi Hagiwara Satoshi Tsukada Toshio Miyawaki Shigeru Tsuchiya Toshihiro Nukiwa 《Respiratory research》2001,2(3):188-5
Background
X-linked agammaglobulinemia (XLA) is a humoral immunodeficiency caused by disruption of the Bruton's tyrosine kinase (BTK) gene. Typical XLA patients suffer recurrent and severe bacterial infections in childhood. 相似文献996.
Site-specific modification of functional groups in genomic hepatitis delta virus (HDV) ribozyme. 总被引:3,自引:0,他引:3
Fumiko Nishikawa Miho Shirai Satoshi Nishikawa 《European journal of biochemistry》2002,269(23):5792-5803
Human hepatitis delta (HDV) ribozyme is one of small ribozymes, such as hammerhead and hairpin ribozymes, etc. Its secondary structure shows pseudoknot structure composed of four stems (I to IV) and three single-stranded regions (SSrA, -B and -C). The 3D structure of 3'-cleaved product of genomic HDV ribozyme provided extensive information about tertiary hydrogen bonding interactions between nucleotide bases, phosphate oxygens and 2'OHs including new stem structure P1.1. To analyze the role of these hydrogen bond networks in the catalytic reaction, site-specific atomic-level modifications (such as deoxynucleotides, deoxyribosyl-2-aminopurine, deoxyribosylpurine, 7-deaza-ribonucleotide and inosine) were incorporated in the smallest trans-acting HDV ribozyme (47-mer). Kinetic analysis of these ribozyme variants demonstrated the importance of the two W-C base pairs of P1.1 for cleavage; in addition, the results suggest that all hydrogen bond interactions detected in the crystal structure involving 2'-OH and N7 atoms are present in the active ribozyme structure. In most of the variants, the relative reduction in kobs caused by substitution of the 2'-OH group correlated with the number of hydrogen bonds affected by the substitution. However G74 and C75 may have more than one hydrogen bond involving the 2'-OH in both the trans- and cis-acting HDV ribozyme. Moreover, in variants in which N7 was deleted, kobs was reduced 5- to 15-fold, it may suggest that N7 assists in coordinating Mg2+ ions or water molecules which bind with weak affinity in the active structure. 相似文献
997.
We found that the gradient of a host-specific attractant, cochliophilin A (5-hydroxy-6,7-methylenedioxyflavone) isolated from the roots of spinach triggered encystment followed by germination of zoospores of Aphanomyces cochlioidesat a concentration less than micromolar order. This compound did not affect the growth and reproduction of this phytopathogen up to 10–6 M concentration in the culture medium. We also observed that mastoparan, an activator of heterotrimeric G-protein could inhibit the motility of zoospores and then strikingly effect encystment followed by 60–80% germination of cysts. Concomitant application of cochliophilin A and mastoparan showed stronger encystment followed by 100% germination of cysts. In addition, we have observed that chemicals interfering with phospholipase C activity (neomycin) and Ca2+ influx/release (EGTA and loperamide) suppress cochliophilin A or mastoparan induced encystment and germination. These results suggest that G-protein mediated signal transduction mechanism may be involved in the differentiation of the A. cochlioides zoospores. This is the first report on the differentiation of oomycete zoospores initiated by a host-specific plant signal or a G-protein activator. 相似文献
998.
999.
1000.
Satoshi Hirohata Lauren W Wang Masaru Miyagi Lin Yan Michael F Seldin Douglas R Keene John W Crabb Suneel S Apte 《The Journal of biological chemistry》2002,277(14):12182-12189
Punctin (ADAMTSL-1) is a secreted molecule resembling members of the ADAMTS family of proteases. Punctin lacks the pro-metalloprotease and the disintegrin-like domain typical of this family but contains other ADAMTS domains in precise order including four thrombospondin type I repeats. Punctin is the product of a distinct gene on human chromosome 9p21-22 and mouse chromosome 4 that is expressed in adult skeletal muscle. His-tagged punctin expressed in stably transfected High-Five(TM) insect cells was purified to apparent homogeneity by Ni-chromatography of conditioned medium. The NH(2) terminus is not blocked and has the sequence EEDRD and so forth as determined by Edman degradation, demonstrating signal peptidase processing. Recombinant epitope-tagged punctin has a calculated mass of 59,991 Da but exhibits major molecular species of 61970 +/- 6 Da and 62131 +/- 5 Da as measured by liquid chromatography electrospray mass spectrometry. Punctin is a glycoprotein based on carbohydrate staining and liquid chromatography electrospray mass spectrometry glycopeptide analysis. Glycosylation occurs at a single N-linked site as demonstrated by altered electrophoretic migration of punctin expressed in the presence of tunicamycin A. Punctin contains disulfide bonds based on antibody accessibility and electrophoretic migration under reducing versus nonreducing conditions. Rotary shadowing demonstrates that punctin is hatchet-shaped having a globular region attached to a short stem. In transfected COS-1 cells, punctin is deposited in the cell substratum in a punctate fashion and is excluded from focal contacts. Punctin is the first member of a novel family of ADAMTS-like proteins that may have important functions in the extracellular matrix. 相似文献